Method of oxidizing mineral hydrocarbons



Patented Apr. 24, 1928.

PATENT OFFICE.

JOSEPH EIDY JAMES, 012 PITTSBURGH, PENN SYLVANIA.

METHOD OF OXIDIZING MINERAL HYDROC ARIBONS.

No Drawing.

In my copending applications, Serial Nos. 272,567; 281,124; 335,940 and 435,355, I have described methods and apparatus for making intermediate oxidation products from aliphatic hydrocarbons, these oxidation products ranging from alcohols through aldehyde alcohols and aldehydes to aldehyde. fatty acids. The temperature in the conver ature range of from 230 up to 450 G., de-- pending on the conditions, the fraction used, etc., through a catalytic layer, composed preferably of oxides or compounds of certain metals, such as molybdenum, vanadium,-- etc. The air is preferably fed in in regulated amounts near thetheoretical combining portion or preferably in excess thereof, and the hot mixture is passed, with or without the addition of a diluting gas, such as steam, through. or over a layer of the catalytic material. The catalysts employed are preferably so complex oxides or compounds of metals having a varying valence, such for, example, as

blue oxides of molybdenum.

The condensed product contains partly oxidizedbodies such as above referred to. The raw material used-may be petroleum,a petroleum fraction, shale oil or a fraction thereof or the product from a low temperature distillation of coal.

Under my present invention, Iy subject m the mineral'hydrocarbon containing bodies of different molecular weights to heat treatment sufficient to convert at least a part thereof into a vapor or gaseous phase, separate from the heavier portions a lighter 6 portion in the vapor or gaseous phase, and while the lighter portion still remains in this phase, mix it with oxygen or oxygen-com taining gas and artially oxidize the same at a. temperature so combustion, and preferably, below a red heat, in a range which produces partial oxidation s roducts.- In one form of my process, Imay troleum or a fraction'thereof, and thus 'vide it into fractions of different at average molecular weights, and partially low that of self-sustained:

I Application filed December 6,1921. Serial No. $420,283.

oxidize such a separated fractionwhile still in thevapor or gaseous phase. In the distillation of crude or topped petroleum, the oil or portions thereof are vaporized in order to separate the oil into fractions of different boiling points. In my present method, I take one or more of these fractions as it is produced in the distilling, mix it with air and subject it to my partial oxidation process, as described in my above named applications, preferably that one embodied in application Serial No. 435,355, filed January 6, 1921, thereby avoiding the re-va'porization of the condensed distillate or fraction.

In carrying 'out the process, the distillation of the crude oil or part of said crude oil is preferably carried out by the well known methods of continuous distillation or intermittent-continuous distillation, where a series of retorts is employed with the oil or 'oil fractions passing through them in series;

although I may employ the process in conncction with intermediate distillation.

In the preferred form, with what is known as continuous distillation or intermittentcontinuous distillatiom} a number of stills are run in series in a continuous manner, t e crude oil being charged into the first still, the temperature of which is maintained at such a point as to distill over a more volatile portion of the oil. The residue from this still travels on to the next still, where a heavier fraction is distilled and so on.

- In the intermittent-continuous method, the process is the same, except that the temperature is varied in the several stills, so that more than one fraction is volatilized and taken oflfrom one or more of the stills. In combining my process with such an opera tion, I lead or divert part or all of the vapors coming from either of the stills orstill systems, without condensing it add the desired amount of air which may be preheated,

if desired, and pass this mixture of hydrocarbon, vapor and air through a catalytic layer, or layers In this preferred method, I admit one part of the air to the mixture passing through the first catalyiic screen, additional air bein admitted fore passing through each 0 the successive catalytic screens or layers. I may also add steam or other diluent, as described therein, for temrature control, etc.- This steam may be admitted to the vaporrmixture before entering screen'No, 1, or it may befractionally m admitted in the same manner to that of the air. The condensing and absorbing systems may be of any desired type.

The advantages of my invention will be obvious, since avoid revaporizing of a petroleum fractionby submitting the desired fraction or fractions while passing in vapor form from the still directly to the catalytic low-temperature oxidation process. In this way, the amount of additional heat, if any heat is imparted'to the air employed, is very much reduced, and in some cases, no additional heat will be necessary. Where it is desirable, a small air preheater may be employed to preheat the air before passing into the mixture flowing to the first catalytic layer or screen. The heat treatment carried out on the mineral hydrocarbon or fraction thereof may be carried to any desirable extent or degree of temperature, so long as the separationof the'lighter and heavier parts sisting of subjecting the same to heat treat 'ment, at least sufiicient toconvert a part thereof into vapor or gaseous phase, separating from heavier portions thereof a li hter portion in the vapor or gaseous phase, t ereafter mixing alighter portion while still in vapor or gaseous phase with a gas contain ing oxygen, passing the vapor-oxygen mixture incontact with a catalyst and partially oxidizing the 'same within a range of temperature below that of continuous self-sustained combustion and which produces partial oxidation products.

- 2. In the treatment of a liquid mineral hydrocarbon containing hydrocarbons of different molecular weights, the steps consisting of subjecting the same to heat treatment,

- at least sufiicient to convert a part thereof into vapor or gaseous phase, separating from heavier portions thereof a lighter portion in the vapor or gaseous phase, and thereafter mixing a lighterportion while still in vapor or aseous phase with oxygen and partially oxidizing t e that of self-sustained combustion and in a range s which produces partial oxidation products. v

3. In the treatment of-a liquid mineral h drocarbon containing hydrocarbons of different molecular weights,'the steps consisting of subjectingthe same to a heat same at a temperature below treatment, at least sufiicient to convert a part thereof into vapor or gaseous phase, separating from heavier portlons thereof a lighter portion in the vapor or gaseous phase, and thereafter mixing a lighter ortion while still in vapor or gaseous'p ass with oxygen and partially oxidizing the same in the presence of a catalyst at a temperature below that of self-sustained com- I bustion and in a range which produces partial oxidation products.

4. In the treatment of a liquid mineral hydrocarbon containing hydrocarbons of different molecular weights, the steps consisting of subjecting the same to heat treatment, at least suiiicient to convert a part thereof into vapor or gaseous phase, separating from heavier portions thereof a lighter portion in the vapor or gaseous phase, and. thereafter mixing a lighter portion while invaporsor aseous "phase with preheated oxygen containing gas,'passing the vapor-oxygen mixture in contact with a catalyst and partially oxidizing the same within a temperature range below that of continuous self-sustained combustion and which produces partial oxidation products.

5. In the treatment of mineral oil contain ing liquid hydrocarbons of different molecular weights, the steps consisting of distilling the sameinto separate fractions, mixing one of the fractions while still in the vapo1 phase with oxygen, and subjecting the mixtureto a partial oxidation process at a tem perature below a red heat.

6. In the treatment of mineral oil containing liquid hydrocarbons of different molecular weights, the steps consisting of distilling the same into separate fractions, mix ing one of the fractions while still in ,th vapor hase with oxygen and a diluent, ant subjecting the mixture to a artial oxidatioz process at a temperature be ow a red heat.

7. In the treatment of mineral oil containing liquid hydrocarbons of different molecular weights, the steps consisting of distilling the same into separate fractions, mixing om of the fractions while still in-the vapo1 phase with preheated oxygen, and subjecting the mixture to a partial oxidation process a a temperature below a red heat,

8. In the. treatment of a liquid minera hydrocarbon containing hydrocarbons of different molecular weights, the steps con sisting of subjecting the same to heat treatment at least sufiicient to convert a pan thereof into vapor or gaseous phase, sep arating from heavier. portions. thereof lighter por-ti6n in the vapor or gaseou: phase, thereafter mixing a-lighter portiox while still-in vapor .or gaseous phase witl oxygen and partially oxldizing the same a a tem erature below a red heat.

9. the treatment of a liquid minera hydrocarbon, "containing hydrocarbons o1 difierent molecularweights, the steps con while still in vapor-or gaseous base withsisting of subjecting the same to heat treatoxygen and partlally 0x1dizing t e same in [ment at least sufiieient to convert a part .the presence of a catalyst and at a .tempera- 10 thereof into vapor'or gaseous phase, sep ture below a red. heat. 1 it 5 arating from heavier portions thereof a In testimony whereof-I have hereunto set lighter portion in the ,vapor or gaseous m hand; phase, thereafter mixing a lighter portion JOSEPH HIDY JAMES. 

